This invention relates to hole cutting apparatus, and more particularly to a hole cutter which can be used to cut holes in a tacky, gum like substance, such as seal rings utilized in surrounding the stoma of an ostomy appliance.
The prior art includes many types of hole cutters and punchers designed for specific material and specific uses. As is well known, there are various ways of forming a hole in a material. One method is by punching the hole by using a solid puncher. The hole is formed by applying pressure, and frequently impulse force, to the solid puncher to knock out a hole in the material. Another well known method of forming holes involves cutting the hollow by using a hole tube having a cutting edge. The tube is pressed down and shears the material being cut. Depending upon the type of material, an appropriate type of cutter or puncher will be selected. For example, if the material is thin and stiff, such as paper or cardboard, a hole puncher can be utilized. On the other hand, if the material is soft, such as fruits and vegetables, a hole cutter will be utilized which shears through the material. Such hole cutters are frequently utilized for removing the core of fruit and/or vegetables.
A more difficult situation occurs when the material to be cut is tacky and sticky, such as for example, clay, gum, pottery, etc. Such material is not hard enough to utilize a puncher since the hole puncher would merely deform the material but would not form a hole therein. On the other hand, the material is not soft enough to be sheared by using a hollow tube hole cutter. In order to form holes in such thick, tacky material, the prior art has suggested various solutions which generally relate to slicing a hole through the material rather than by just shearing it. Such prior art devices have suggested forming serrated edges or notches along the cutting edge of the hollow tube. The hollow tube is then inserted into the clay-like material and the tube is rotated, so that the sharpened, serrated edges or notches can slice around the material and form a hole therein.
However, because of the serrated edges, the hole cutters have become more expensive to manufacture and because rotation of the hole cutters is required, they become more difficult to use. Furthermore, the serrated or notched edges may be suitable when the material is thick, such as in connection with pottery. However, when a very thin layer of this material is to be cut, the serrated edge will not provide a smooth cut and a rather rough edge will result. Also, it will frequently deform the material while making the hole therein.
One particular material is most difficult to work with is the seal ring which is placed around the stoma of an ostomy appliance. An ostomy generally refers to the surgical operation which creates a new outside opening for body wastes called a stoma. Various types of ostomy operations are well known, such as the colostomy the ileostomy and the ureterostomy. In all cases, an opening is made in the body to permit removal of waste products. A person with such a stoma must usually wear an ostomy appliance, which is a collecting device. The appliance must be connected to the stoma to prevent leakage from the stoma, and at the same time not exert pressure on the stoma. One of the most important aspects of taking care of the patients well being is to properly measure the stoma to select the proper sized appliance. If the appliance has too small an opening it will place a strain on the stome. Too large an opening will expose the skin around the stoma and allow irritation to take place. In order to properly fit the appliance to the stoma, a seal ring is utilized. This seal ring is made out of a gum like material chosen for its ability to protect the skin against the inflaming digestive fluids. The seal is frequently made out of a type of karaya gum powder which is sticky and tacky. The material is affected by heat and moisture so that in winter weather the seal will be firm and less tacky while during warmer weather it will again become moist and tacky.
Since stomas can be made in various sizes, the hole in the seal ring must fit exactly the stoma. One method is to purchase precut seal rings and place them between the stoma and the appliance. However, such precut seal rings are extremely expensive since they must be formed in numerous sizes. Also, since only a limited number of such sizes can be made available, many times there will be a slight space between the seal and the stoma causing difficulty to the patient. Another method is to buy a solid circular seal and for the patient to form the hole in the seal by himself, in accordance with the stoma size needed. This method is generally desired since it izs cheaper to buy a standard circular seal, and also the hole can be formed to exactly fit the stoma. However, it is extremely difficult to make a hole in this gum like material. In most cases a scissor is utilized, but as is well known, it is difficult to make a perfect circle using a scissor. Prior art hole cutters are also difficult to utilize since the material of the seal is a substance which is awkward for both hole punchers and hole cutters, and using a hole cutter which must be rotated, tends to distort the ring.
The problem is even further aggravated in that the seal usually comes in a plastic case. In order to make the hole in the ring, it is necessary to either cut through the plastic case together with the seal, or to try to cut the hole in the seal without cutting into the plastic case. This entire situations presents a most difficult problem for hospitals, clinics, as well as individual patients. The cutting of holes in the gum like seals has therefore been a very time consuming and taxing task which provides much aggravation to all those requiring such seals.